1. Field of the Invention
The present invention relates to cables, and more particularly to cables for carrying signals, for example from remote sensors.
2. Description of Related Art
Cables such as coaxial cables, twisted shielded cables, or the like, are commonly used to carry signals. For example, in systems using tuned resonant sensors, a cable can connect between a remote sensor and a diagnostic or control system. Various errors can occur in such systems. Various approaches have been taken to address some types of errors. For example, commonly assigned U.S. Patent Application Publication No. 2012/0194201, which is incorporated by reference herein in its entirety, describes solutions for frequency based fault detection.
Many common sensors and systems, such as RTDs, LVDTs, and resolvers, are sensitive to errors introduced due to the effects of the cable/harness. Resonant based inductive sensors, for example knock sensors, eddy current sensors or oil debris sensors, may be particularly sensitive to shifts in resonance due to cable capacitance. It is common for control systems to compensate for the cable error if the cable type and length are fixed, thus, controlling the resulting cable parasitic that causes the error. For a resonant based sensor, a typical compensation method is to tune the resonance to the known cable length or to calibrate accordingly. However, it is a more difficult problem to compensate for the error if the cable type or length changes for different system installations.
Such conventional methods and systems have generally been considered satisfactory for their intended purpose. However, there is still a need in the art for systems and methods that allow for improved compensation for cable/harness effects. There also remains a need in the art for such systems and methods that are easy to make and use. The present invention provides a solution for these problems.